Cable constructions of the above-mentioned type are rather well known at present in connection with various cables, e.g. optical cables. The existing non-metallic optical cable constructions require several process steps, some of which may be very slow. Expensive reinforcements added separately to the constructions may require the use of additives in order that better grip or waterproofness could be obtained, which further retards the manufacturing process. In order to improve the thermal stability of the cable construction, i.e. to reduce the thermal compression, it is often also necessary to use rod-like reinforcement elements. The use of such elements results in certain, not always positive, properties of the cable: flexural stiffness, greater dimensions, high price, etc. It is particularly difficult to use such separate composite rods in so-called center pipe constructions, in which the rods must be mounted on the outer circumference of the core, and there must be at least two of them for reasons of symmetry.
If the cable is to provide mechanical protection against rodents and termites and resistance to oil and chemicals, and/or to have barrier properties against moisture and gases, it is necessary to use expensive semi-finished products, which must be processed in separate, often complicated process steps. This complicates the construction and increases the costs of the product.